10 SCIENCE Quarter 1

LEARNER’S MATERIAL

Republic Act 8293, section 176 states that: No copyright shall subsist

in any work of the Government of the Philippines. However, prior approval of

the government agency or office wherein the work is created shall be necessary

for exploitation of such work for profit. Such agency or office may, among other

things, impose as a condition the payment of royalties.

Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand

names, trademarks, etc.) included in this book are owned by their respective

copyright holders. Every effort has been exerted to locate and seek permission

to use these materials from their respective copyright owners. The publisher

a n d a u t h o r s d o n o t r e p r e s e n t n o r c l a i m

ownership over them.

This module is a resource of information and guide in

understanding the Most Essential Learning Competencies (MELCs). Under-

standing the target contents and skills can be further enriched thru the K to

12 Learn ing Mater ia ls and o ther supp lementary

materials such as worksheets/activity sheets provided by schools and/or

Schools Division Offices and thru other learning delivery modalities including

radio-based and TV-based instruction (RB/TVI).

CLMD CALABARZON

WEEK

1 & 2

Science

Grade 10

Regional Office Management and Development Team: Job S. Zape, Jr., Ma. Leonora Natividad, Romyr L. Lazo, Fe M. Ong-Ongowan, Lhovie A. Cauilan,

Ephraim L. Gibas

Schools Division Office Development Team: Joesel D. Dariagan, Maria Ria S. Calub,

Leylanie V. Adao, Gemma G. Cortez , Fernando Mamauag, Jr.

Science Grade 10

PIVOT IV-A Learner’s Material

First Quarter

First Edition, 2020

Published by: Department of Education Region IV-A CALABARZON

Regional Director: Wilfredo E. Cabral

Assistant Regional Director: Ruth L. Fuentes

PIVOT 4A CALABARZON

For the Parents/Guardian

This module aims to assist you, dear parents, guardians, or siblings of

the learners, to understand how materials and activities are used in the new nor-

mal. It is designed to provide the information, activities, and new learning that

learners need to work on.

Activities presented in this module are based on the Most Essential

Learning Competencies (MELCs) for English as prescribed by the Department of

Education.

Further, this learning resource hopes to engage the learners in guided and

independent learning activities at their own pace and time. Furthermore, this also

aims to help learners acquire the needed 21st century skills while taking into

consideration their needs and circumstances.

You are expected to assist the child in the tasks and ensure the learner’s

mastery of the subject matter. Be reminded that learners have to answer all the

activities in their own notebook.

Guide in Using PIVOT Learner’s Material

For the Learners

The module is designed to suit your needs and interests using

the IDEA instructional process. This will help you attain the prescribed

grade-level knowledge, skills, attitude, and values at your own pace

outside the normal classroom setting.

The module is composed of different types of activities that are

arranged according to graduated levels of difficulty—from simple to

complex. You are expected to answer all activities on separate sheets

of paper and submit the outputs to your respective teachers on the

time and date agreed upon.

PIVOT 4A CALABARZON

Parts of the

LM Description

What I need

to know

The teacher utilizes appropriate strategies in presenting

the MELC and desired learning outcomes for the day or

week, purpose of the lesson, core content and relevant

samples. This allows teachers to maximize learners

awareness of their own knowledge as regards content and

skills required for the lesson

What is new

What I know The teacher presents activities, tasks , contents of value

and interest to the learners. This shall expose the learners

on what he/she knew, what he /she does not know and

what she/he wanted to know and learn. Most of the activi-

ties and tasks must simply and directly revolved

around the concepts to develop and master the skills or

the MELC.

What is in

What is it

What is more The teacher allows the learners to be engaged in various

tasks and opportunities in building their KSA’s to

meaningfully connect their learnings after doing the tasks

in the D. This part exposes the learner to real life situa-

tions /tasks that shall ignite his/ her interests to meet

the expectation, make their performance satisfactory or

produce a product or performance which lead him/ her

to understand fully the skills and concepts .

What I can

do

What else I

can do

What I have

learned

The teacher brings the learners to a process where they

shall demonstrate ideas, interpretation , mindset or val-

ues and create pieces of information that will form part

of their knowledge in reflecting, relating or using it effec-

tively in any situation or context. This part encourages

learners in creating conceptual structures giving them

the avenue to integrate new and old learnings.

What I can

achieve

Intr

oducti

on

Develo

pm

en

t E

ngagem

en

t A

ssim

ilati

on

PARTS OF PIVOT LEARNER’S MATERIAL

PIVOT 4A CALABARZON

In this lesson, you shall know the distribution of active volcanoes,

earthquake, epicenters, major mountain belts and further explain the plate tectonic theory after gaining a full understanding of the concepts embedded in

the many activities on this lesson.

I

6

Weeks

1-3

Read and study the picture. Do you know the location of active volcanoes

in the Philippines ? Can you locate them in the map?

Our country is situated in the Pacific Ring of Fire where the oceanic plate

and several smaller micro plates sub-ducting along the Philippine plate and sever-

al microplates along the Philippine Trench to the East and smaller trenches to the

West. To date, as per report of the PHILVOCS (Philippine Institute of Volcanology

and Seismology), there are 53 active volcanoes in the Philippines characterized by

two major NS trending arcs – the Luzon and Mindanao Volcanic Arcs. This makes

the country’s tectonic setting complex aside from having a number of small plates

squeezed between two convergent plate margins, separated by small subduction

zones and major transform faults.

Active Volcanoes

Distribution of Active Volcanoes, Earthquake

Epicenters, and Major Mountain Belts

PIVOT 4A CALABARZON

Some volcanoes in the Philippines are active or dormant. We describe

volcanoes as dormant and active based from their frequency of eruptions. Those that erupt regularly are called active and those that have erupted in the past

and are inactive are called dormant.

Some Active and

Dormant Volcanoes Location

Name Coordinates Province

Banahaw 14°04′N 121°29′E Laguna, Quezon

Bulusan 12°46′12″N 124°03′00″E Sorsogon

Camiguin

de Babuyanes 18°49′48″N 121°51′36″E Cagayan

Hibok‑Hibok 9°12′11″N 124°40′23″E Camiguin

Iraya 20°28′08″N 122°00′36″E Batanes

Iriga 13°27′25″N 123°27′25″E Camarines Sur

Kanlaon 10°24′43″N 123°07′55″E Ne-gros Occidental/

Oriental

Makaturing 7°38′49″N 124°19′12″E Lanao del Sur

Matutum 6°22′N 125°04′E South Cotabato

Mayon 13°15′25″N 123°41′06″E Albay

Pinatubo 15°08′N 120°21′E Zam-

bales,Tarlac,

Pampanga

Taal 14°00′07″N 120°59′35″E Batangas

Taal, Pinatubo and Mayon volcanoes are the familiar volcanoes of the

country in terms of their eruptions. They are formed when pieces of earths crusts called plates smash and buckle up through a process called plate

tectonics. Some form mountain ranges or hill ranges arranged in a line and connected by high ground. A group of mountain ranges with similarity in

form , structure and alignment is called a mountain belt.

There are mountain ranges closest to a certain volcano. Say for example, for Taal Volcano, they are Mount Macolod (3107 ft.) which is 7

miles away from Taal, Mt. Talamitan (2310 ft.), 17.3 miles away from Taal,

Mount Panay (1,644 ft.) 22.2 miles from Taal and San Pablo Volcanic Field (3576 ft.) which is 22.2 miles away from Taal. Can you name the mountain

ranges of other active volcanoes in the country ?

The world's tallestformplatesprocess called plate tectonics, and buckle up like the hood of a car in a headcollision.

7

PIVOT 4A CALABARZON

Find the Epicenter

(Adapted and modified from the Learner’s Material)

Materials:

Hypothetical records of earthquake waves

Philippine map

Drawing compass and ruler

Marking pens (3 different colors)

Procedure:

Study the data showing the difference in the arrival time of P-wave

and S-wave on three seismic recording stations.

1. Compute the distance of the epicenter from each of the stations using

this formula:

d = time difference x 100 km

8 seconds

where: d = distance (km)

td = time difference in the arrival time of P-wave and S-wave (seconds)

This formula is suited because 8 seconds is the interval between the times

of arrival of the P-wave and S-wave at a distance of 100 km.

2. Choose one of the recording stations and measure the computed dis-

tance on the scale (the scale of the map is 1 cm: 100 km). Set your

compass for that computed distance. Center your compass on the sta-

tion you have chosen. Draw a circle.

3. Repeat steps 3 and 4 for the rest of the stations. You should get three

circles that intersect or nearly intersect at a point. This intersection is

Recording station

Time difference in

the arrival time of P-

wave and S-wave

Distance of epicen-

tre from the station

(km)

Occidental Mindoro 40

Samar 32

Zambonga del Norte 36

Learning Task 1: Study the activity. Follow the procedure before answering the

questions .

8

PIVOT 4A CALABARZON

Determining the Arrival Times between P -wave and S -wave

Procedure:

a) Line up the ruler or a piece of scrap paper vertically on the epicenter

distance given.

b) Mark the locations where the P-wave and S-wave intersect your ruler

or scrap paper.

C )Line up the ruler or scrap paper on the y-axis with one point on the 0

minute mark.

d) The second mark will indicate the difference in arrival time

Seismologist can determine the difference in arrival times between the

P-wave and the S-waves

Seismic waves are the waves of energy caused by the sudden break-ing of rock within the earth or an explosion. They are the energy that travels

through the earth and is recorded on seismographs. There are several dif-ferent kinds of seismic waves. These waves move in different ways. Body

waves can travel through the earth's inner layers while surface waves can

only move along the surface of the planet like ripples on water. Earthquakes radiate seismic energy as both body and surface waves. Traveling through

the interior of the earth, body waves arrive before the surface waves emitted by an earthquake. These waves are of a higher frequency than surface

waves. The first kind of body wave is the P wave or primary wave. This is the fastest kind of seismic wave, and, consequently, the first to 'arrive' at a

seismic station. The P wave can move through solid rock and fluids, like

water or the liquid layers of the earth. It pushes and pulls the rock it moves through just like sound waves push and pull the air. P waves are also

known as compressional waves, because of the pushing and pulling they do. Subjected to a P wave, particles move in the same direction that the

wave is moving in, which is the direction that the energy is traveling in, and is sometimes called the direction of wave propagation.

Learning Task 2: Study the activity. Follow the procedures indicated in

the activity before answering the questions.

9

PIVOT 4A CALABARZON

Draw the location of the epicenter of an earthquake in Carmona, Silang, GMA

Cavite if the hypothetical distance of epicenter in Carmona is 300 Km, Silang is

200km, and GMA is 200km. Draw this in your notebook

Scale

1cm=100Km

Learning Task 3: Study the picture. Follow the procedures indicated in the

activity before answering the questions.

Seismologists use triangulation to find the epicenter of an earth-

quake. When seismic data is collected from at least three different locations, it can be used to determine the epicenter by where it intersects. Every

earthquake is recorded on numerous seismographs located in different di-rections. Each seismograph records the times when the first (P waves) and

second (S waves) seismic waves arrive. From these, seismologist can deter-mine how fast the waves are traveling. Knowing this helps them calculate

the distance from the epicenter to each seismograph.

10

PIVOT 4A CALABARZON

D

Study the graph. Make use of the four questions to learn more about the

concepts of distance graph .

1. An epicenter station is 4,000 km away. How long after the first P-wave did

the first S-wave arrive?

2. An epicenter station is 5,600 km away. How long after the first P-wave did

the first S-wave arrive?

3. How far can an S-wave travel in 6 minutes 40 seconds?

4. How far can a P-wave travel in 6 minutes 40 seconds?

Distance-Time Graph

Learning Task 4: Study the activity. Follow the procedures indicated in the

activity before answering the questions.

Distance -time graph is a graph wherein the gradient of the line is

equal to the speed of the object. The greater the gradient ( steeper line), the

faster the object is moving. If an object moves a along a straight line, the dis-

tance travelled can be represented by a distance time graph.

11

PIVOT 4A CALABARZON

Drawing by : Joesel D. Dariagan

Descriptions

A. Earthquake

Epicenter

1.

2.

B. Active

Volcano

1.

2.

C. Mountain

Range

1.

2.

Learning Task 5: Complete the table below. Using the picture to

describe its observable or physical characteristics.

12

PIVOT 4A CALABARZON

Learning Task 6: Below is a map showing the location of the active

volcanoes, earthquake prone areas and mountain ranges in the Philippines.

List them down. Describe their locations.

Active Volcanoes

Luzon

Visayas

Mindanao

13

PIVOT 4A CALABARZON

Location of active volcanoes, earthquake epicenters, and mountain

ranges in different Continents

Questions:

1. Based on the map, list down the places where you can find the following;

a. volcanoes

b. earthquake epicenters

c. mountain ranges

2. Why do active volcanoes, mountain ranges/folded mountains, and earth-

quake zone are located in the same place?

3. Explain why those places in the map have active volcanoes, earthquake

epicenters and mountain ranges.

Learning Task 7: Using the world map, locate and list down the location of

active volcanoes , earthquake zones and mountain ranges in the world.

14

PIVOT 4A CALABARZON

Earthquake is the shaking of the earth’s surface that often causes a great damage. Epicenter is the part of the earth’s surface that is directly

above the place where earthquake starts. Volcanoes are a mountain with a hole in the top or side that sends out rocks, ash, lava, and etc. and moun-

tain ranges are succession of many closely spaced mountains covering a particular portion of earth. The location of most active volcanoes, earth-

quake epicenters, and mountain ranges are found in the Pacific Ring of Fire

or in the Pacific Ocean basin.

Earthquake zones

Luzon Visayas Mindanao

Active volcanoes

Luzon Visayas Mindanao

Mountain ranges

Luzon Visayas Mindanao

Philippines

Learning Task 8: Complete the concept map. Copy this in your notebook. Use

the paragraph before the concept map as your guide to look for more information

from other sources.

E

A

Learning Task 7: Draw a simple map and describe the distribution of active

volcanoes, earthquake epicenter and major mountain belts in CALABARZON.

Use your notebook for your answer.

15

PIVOT 4A CALABARZON

I

In the previous lesson, you’ve learned about how to find the

earthquake’s epicenter using the triangulation method and distance-time

graph. The characteristics and locations of active volcanoes, mountain

ranges, and earthquake zones (epicenter) were also discussed using a

map. This time, in this lesson, you will identify and describe the different

types of plate boundaries that will help you to understand the occurrence

of an earthquake and other geologic activities.

Study the pictures showing the fault line in the plate boundaries

Figure 1

Figure 2

Figure 3

Describe each figure. How does each figure differ? How are the

figures similar ? What did you notice with the spaces in between the

two plates ?

Week

4

Types of Plate Boundaries

Lesson

16

PIVOT 4A CALABARZON

In the pictures, you can say that, plates can move apart at

a boundary. Earthquakes occur along the fractures that appear as

the plates move apart.

The three types of plate boundaries are convergent, divergent

and transform. Convergent boundary a boundary in which two plates

move toward each other, causing one of the slabs of the lithosphere to

subduct beneath an overriding plate. Divergent boundary is a region

where the crustal plates are moving apart. Transform fault boundary

is a boundary produced when two plates slide past each other.

Below is a picture showing the fault lines in the Philippines.

During earthquake, it is presumed that plates along the fault line

moved and the occurrence of such earthquake can also affect far

from the edges of tectonic plates, along faults. Faults are cracks in

the lithosphere caused by the stresses created as sections of

a plate (or two plates) which are moving in different directions. In this

17

PIVOT 4A CALABARZON

D

Learning Task 1: Study pictures A to D. Describe each of them.

Reread again the pages of this module to help you create an answer.

Write your answer in your notebook.

Picture A

Picture B

Picture C

18

PIVOT 4A CALABARZON

Picture D

Type of plate bounda-

ries

How does it look like?

(draw)

Describe each type of

plate boundaries in 3

words

Convergent

a. continental-

continental

b. oceanic-oceanic

c. oceanic-continental

Divergent

Transform

Learning Task 2: Complete the table by copying it in your notebook.

19

PIVOT 4A CALABARZON

Location of Plate Boundaries

Study the world map below and answer the questions;

What type of plate boundaries exist in the following plate?

a. Eurasian and Philippine plates

b. Antarctic and South American plates

c. Antarctic and Australian Plates

d. South American and African plates

e. North American and Eurasian plates

f. South American and Antarctic plates

Learning Task 3: Study the world map and answer the following

questions in your notebook.

20

PIVOT 4A CALABARZON

E

Learning Task 4: Answer this question in your notebook.

If you are given the chance to become a cartographer (a person who

makes maps) and you are asked to make a map, what legend will you use in

order to inform the people about the location of different types of plate

boundaries? Illustrate your answer in your notebook.

A

Learning Task 5 : Choose the letter of the correct answer.

1. Which of the will form when two tectonic plates are moving toward each

other?

A. convergent B. divergent C. tectonic D. transform

2. Nazca plate and South American plate is an example of what plate

boundary?

A. convergent B. divergent C. tectonic D. transform

3. What type of plate boundary formed if two plates moved away from each

other?

A. convergent B. divergent C. tectonic D. transform

4. What type of plate boundary exists in two sliding plates?

A. convergent B. divergent C. tectonic D. transform

5. What type of plate boundary exists on a certain island if you can find rift

valley?

A. convergent B. divergent C. tectonic D. transform

6. A. convergent B. divergent C. transform D. normal

7. What type of plate boundary exists on a certain island if you can find

mountain ranges?

A. convergent B. divergent C. tectonic D. transform

21

PIVOT 4A CALABARZON

Processes that Occur Along Plate Boundaries

Lesson

I

In the previous lesson you’ve learned about the different

types of plate boundaries, oceanic-oceanic, continental-

continental, continental-oceanic convergent, divergent, and

transform plate boundaries and determination of the locations of

different types of plate boundaries across the continents.

This time, you will learn the different processes and geologic

features along plate boundaries that slowly shaped the Earth’s

surface give rise to mountain ranges, volcanoes, earthquake belts

and other geologic features for you to explain the processes that

occur along convergent, divergent, and transform-fault boundaries.

Now, what process occurs along convergent plate

boundaries? What geologic features formed when two plates moved toward each other? What are/is the reason/s why do plates move

toward each other?

In some ways, our planet resembles like a giant jigsaw puzzle because its outer surface is composed of about 20 tectonic plates with enormous sections that roughly fit together and meet

a t p l a c e s c a l l e d p l a t e b o u n d a r i e s .

Plate boundaries are important since they are often associated with earthquakes and volcanoes. When Earth’s tectonic

plates grind past one another, enormous amounts of energy can be released in the form of earthquakes. Volcanoes are also often found near plate boundaries because molten rock from deep within

Earth can travel upward at these intersections between plates.

.

Week

5

22

PIVOT 4A CALABARZON

D

Convergent Plate Boundary

When continental and oceanic

plates collide, the thinner and denser oceanic plate is overridden by the

thicker and less dense continental plate. The oceanic plate is forced down into

the mantle in a process known as "subduction." As the oceanic plate descends, it is forced into higher

temperature environments. At a depth of about 100 miles (160 km), materials

in the subducting plate begin to approach their melting temperatures

and a process of partial melting begins.

When a convergent boundary occurs between two oceanic

plates, one of those plates will subduct beneath the other. Normally the older plate will subduct because of its higher density. The

subducting plate is heated as it is forced deeper into the mantle, and

at a depth of about 100 miles (150 km) the plate begins to melt.

Magma chambers are produced as a result of this melting, and

the magma is lower in density than the surrounding rock material. It begins ascending by melting and fracturing its way through the

overlying rock material. Magma chambers that reach the surface break

through to form a volcanic eruption cone.

In the early stages of this type of boundary, the cones will be deep beneath the ocean surface but later grow to be higher than sea level. This produces an island chain. With continued development the

islands grow larger, merge, and an elongate landmass is created.

Learning Task 1: Read and study the different types of plate

boundaries. Answer the questions that follow after the discussion of the

contents on plate boundaries.

23

PIVOT 4A CALABARZON

Divergent Plate Boundary

When a divergent boundary occurs beneath oceanic lithosphere, the

rising convection current below lifts the lithosphere, producing a mid-ocean

ridge. Extensional forces stretch the lithosphere and produce a deep fissure.

When the fissure opens, pressure is reduced on the super-heated mantle

material below. It responds by melting, and the new magma flows into the

fissure. The magma then solidifies and the process repeats itself.

1. What process occurs along divergent plate boundary?

2. What geologic features formed when two plates moved away from each

other?

3. Compare rift valley from mid-ocean ridge. Explain your answer.

24

PIVOT 4A CALABARZON

Transform plate boundary

Transform Plate Boundaries are locations where two plates

slide past one another. The fracture zone that forms a transform

plate boundary is known as a transform fault. Most transform faults

are found in the ocean basin and connect offsets in the mid-ocean

ridges. A smaller number connect mid-ocean ridges and subduction

zones.

Transform faults can be distinguished from the typical strike-

slip faults because the sense of movement is in the opposite direction

(see illustration). A strike-slip fault is a simple offset; however, a

transform fault is formed between two different plates, each moving

away from the spreading center of a divergent plate boundary. When

you look at the transform fault diagram, imagine the double line as a

divergent plate boundary and visualize which way the diverging

plates would be moving.

Questions:

1. What process occurs along transform fault plate boundary?

2. How do plate boundaries become transform fault?

3. Why transform fault is occurs in lithosphere?

25

PIVOT 4A CALABARZON

E

A. B. C.

Subduction Mountain ranges Volcanic arc Rift valley Fault Mid-ocean ridge Fissures Fracture zone

Magma chamber Collision Spreading Trench

Slip

Learning Task 2 : Study the pictures and group of words below. Use the

words to explain the processes that occur in each picture. Write your answer

in your notebook.

Learning Task 3: Explain the processes along plate boundaries

thru the use of a graphic organizer below. Write your answer in your

notebook.

26

PIVOT 4A CALABARZON

Choose the letter of the correct answer.

1. What geologic features resulted from the collision of the two continental

plates?

A. volcanic island arc C. mountain

B. fault D. earthquake epicenter

2. The following are the secondary effect of movement of the plates, which of

the following is NOT?

A. tsunami C. landslide

B. fire D. earthquake

3. Which of the following is the result of the collision of two oceanic plates?

A. trench C. rift valley

B. volcano D. fault line

4. What geologic feature produced in the convergence of two continental plates?

A. folded mountains C. Rift valleys

B. Island arcs D. Trenches

5. Which of the following can we expect to find at a mid-ocean ridge?

A. relatively young rocks C. very ancient rocks.

B. reverse fault D. thick accumulation of sediments

6. Why does the oceanic crust sink beneath the continental crust at then

subduction zone?

A. The oceanic crust has a greater density.

B. The oceanic crust is pulled downward by Earth’s magnetic field.

C. The oceanic crust is pushed from the ridge.

D. The continental crust has a denser composition.

7. What happens when two oceanic plates collide?

A. The hot spot will form.

B. The volcano island arc will form.

C. The volcanoes on the edge of a continent will form.

D. The volcano along the mid-oceanic ridge will form.

8. What is produced in the convergence of two continental plates?

A. folded mountains C. rift valleys

B. island arcs D. trenches

Learning Task 4: Read the questions below. Pick the best letter for

your answer in each item. Write your answer in your notebook.

A

27

PIVOT 4A CALABARZON

9. Which of the following is NOT a geologic process that occurs along convergent

boundaries?

A. earthquakes C. tornado

B. mountain-building D. volcanism

10. What topographic feature is formed in divergent boundary?

A. fault C. rift valley

B. mountain D. volcano

11. If you will visit a place in the Pacific known to be along converging plates,

which of

these should you not expect to see?

A. active volcanoes C. rift valley

B. mountain ranges D. volcanic

12. Which of the following geologic features formed in the divergent plate

boundary?

A. San Andreas fault C. Mt. Himalayas

B. Sierra Madre D. Great Rift Valley of East Africa

13. Which of the following is not a divergent plate boundary?

A. Mid-ocean ridge C. spreading of sea floor

B. Mt. Himalayas D. Rift Valley

14. What geologic feature forms when a divergent boundary occurs beneath the

oceanic

lithosphere and there is rising convection current below lifts the

lithosphere?

A. mountain belts C. volcanic arcs

B. mid-ocean ridge D. fault line

15. When a convergent boundary occurs between two oceanic plates, what will

happen to

one of those plates?

A. The plate will subduct beneath to the other plate.

B. The plate will subduct toward to the other plate.

C. The plate will move away to the other plate.

D. The plate will move toward to the other plate.

28

PIVOT 4A CALABARZON

Causes of Plate Movement

Lesson

I

In this lesson, you will able you to evaluate the different theories

explaining the possible causes of tectonic plates, understand the convection

current and importance of tectonic plates to the survival of earth and its

inhabitants. It will also help you to describe the possible causes of plate

movement and explain these causes.

Week

7

Study the comic strip below. What did you notice? What are they telling

about each other ?

29

PIVOT 4A CALABARZON

Another is Plate Tectonics theory wherein it describes the large-scale mo-

tion of seven large plates and the movements of a larger number of smaller plates

of the Earth’s lithosphere, since tectonic processes began on Earth between 3.3

and 3.5 billion years ago. It deals with the dynamics of Earth’s outer shell- the

Lithosphere- that revolutionized Earth sciences by providing a uniform context

for understanding mountain-building processes, volcanoes, and earthquakes as

well as the evolution of Earth’s surface and reconstructing its past continents

and oceans.

Others say that it is due to convection currents. Convection currents be-

neath the plates are believed to be responsible for plate movement. The source of

energy responsible for generating the heat and convection currents that move the

plates is most likely radioactivity deep in Earth's mantle. Mantle convection cur-

rents, ridge push and slab pull are three of the forces that have been proposed as

the main drivers of plate movement .

Do you know that there are number of competing theories that attempt to

explain what drives the movement of tectonic plates. Three of the forces that have

been proposed as the main drivers of tectonic plate movement are:

1. mantle convection currents— warm mantle currents drive and carry

plates of lithosphere along a like a conveyor belt;

2. ridge push (buoyant upwelling mantle at mid-ocean ridges) — newly

formed plates at oceanic ridges are warm, and so have a higher ele-

vation at the oceanic ridge than the colder, more dense plate materi-

al further away; gravity causes the higher plate at the ridge to push

away the lithosphere that lies further from the ridge

3. slab pull — older, colder plates sink at subduction zones, because

as they cool, they become more dense than the underlying mantle.

The cooler sinking plate pulls the rest of the warmer plate along be-

hind it.

On the other hand, recent research has shown that the major driving

force for most plate movement is slab pull, because the plates with more of their

edges being sub-ducted are the faster-moving ones. However ridge push is also

presented in recent researches to be a force that drives the movement of plates.

With these, try to do more research on these ideas for you to have a full un-

derstanding on these concepts.

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Learning Task No. 1: Refer to the discussion above about Plate Tectonic Theo-

ry. Write a short paragraph regarding the movement of tectonic plates. Writre

your answer in your notebook.

D

1. Based from the picture, what do you think are the causes of plate move-

ment? Describe movement of plates.

2. Explain why plates are moving?

Learning Task 2 :Study the two pictures. Answer the questions below

each picture. Write your answers in your notebook.

1. In the cycle shown, is mantle made of silicate rocks? Why ?

2. Why do mantle rock rises?

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E

Article 1

As a substance like water is heated, the less dense particles rise while

denser particles sink. Once the hot less dense particles cool down, they sink,

and the other less dense particles rise. This continuous process is called

convection current. This is exactly what happens in the Earth’s mantle. The

hot, less dense rising material spreads out as it reaches the upper mantle

causing upward and sideward forces. These forces lift and split the lithosphere

at divergent plate boundaries. The hot magma flows out of the mantle and cools

down to form the new ocean crust. The downward movement of the convection

current occurs along a convergent boundary where the sinking force pulls the

tectonic plate downward.

The convection currents rotate very slowly, as they move and drag the

plates along. Because of convection current, the tectonic plates are able to

move slowly along the tectonic boundaries, pushing each other, sliding past

each other and drifting away from each other.

As an oceanic crust moves away from a divergent boundary, it becomes

denser than the newer oceanic crust. As the older seafloor sinks, the weight of

the uplifted ridge pushes the oceanic crust toward the trench at the subduction

zone. This process is called ridge push.

Slab pull is the other possible process involved in the tectonic plate

movement. The weight of the subducting plate pulls the trailing slab into the

subduction zone just like a tablecloth slipping off the table and pulling items

with it. Now that you understand what happens inside the Earth and its effects

on the Earth’s surface, you should be able to realize that the tectonic activities

at the surface just like volcanic eruptions and earthquakes are inevitable. You

should view the Earth as a dynamic planet and still the most fascinating planet

for it offers you a home that no other planet can. Since you can’t prevent these

tectonic activities from happening, the following performance task will enable

you to contribute meaningfully in minimizing the damage that these

phenomena can bring.

If you are a geologist, what theory will you present to describe the `

movements of plates?

Learning Task 2 : Study the articles below. Answer the questions .

Write your answer in your notebook.

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Article 2 : Importance of Plate Movement

Our planet is changing before our eyes, and as a result, many species are

living on the edge. Research by astronomers at the Harvard-Smithsonian Center

for Astrophysics, shows that if Earth had been slightly smaller and less massive,

it would not have plate tectonics - the forces that move continents and build

mountains. And without plate tectonics, life might never have gained a foothold.

"Plate tectonics are essential to life as we know it," said Diana Valencia of

Harvard University. "Our calculations show that bigger is better when it comes

to the habitability of rocky planets."

Plate tectonics -the movement of huge chunks, or plates, of a planet's

surface- are crucial to a planet's habitability because they enable complex

chemistry and recycle substances like carbon dioxide, which acts as a

thermostat and keeps Earth balmy. Carbon dioxide that was locked into rocks is

released when those rocks melt, returning to the atmosphere from volcanoes and

oceanic ridges. "Recycling is important even on a planetary scale," Valencia

explained.

Valencia and her colleagues, Richard O'Connell and Dimitar Sasselov (Harvard

University), have examined the extremes to determine whether plate tectonics

would be more or less likely on different-sized rocky worlds. In particular,

focusing on "super-Earths"-planets more than twice the size of Earth and up to

10 times as massive.

New research indicates that a massive impact may have happened to our

planet that may have made the Earth a friendlier place for life because it

corresponds with this planet's establishment of plate tectonics. About 3.26

billion years ago, an object between 23 and 26 miles wide (37 and 58 kilometers)

crashed into the Earth somewhere and left geological evidence behind in South

Africa. ( Source : http://www.dailygalaxy.com/my_weblog/2014/05/without-plate-tectonics-life-

on-earth-might-never-have-gained-a-foothold-harvard-smithsonian-center-.html)

What do you think will happen to earth if tectonic plates are not

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In 1912, Alfred Wegener (pronounced as vey-guh-nuhr), a German

meteorologist, proposed a theory that about 200 million years ago, the

continents were once one large landmass. He called this landmass Pangaea, a

Greek word which means “All Earth.” This Pangaea started to break into two

smaller supercontinent called Laurasia and Gondwanaland during the Jurassic

Period. These smaller supercontinents broke into the continents and these

continents separated and drifted apart since then. Wegener searched for

evidences to support his claim. He noticed the fit of the edges of the continents

on the opposite sides of the South Atlantic. His evidence to the Continental Drift

Theory includes the distribution of fossils in different continents, rock features,

and ancient climates.

Technology (192-1950)- the SONAR (Sound Navigation and Ranging) system is a

device that bounces sound waves off underwater objects and then records the

echoes of these sound waves. It allowed scientist to map the mid-ocean ridges.

In the 1950s scientists used magnetometers to detect magnetic variations on

the ocean floor. Age acting rocks helped prove that mid-ocean ridges create new

sea floor.

Arthur Holmes (1929) was a British geologist. He suggested that thermal

convection currents in the mantle were the force moving the continents.

Ship Atlantis (1931-1966)- Atlantis was the first ship built specifically for

marine biology, geology, and oceanographic. The first Woods Hole

Oceanographic Institution (WHOI) research ship. The ship began working in

1931 and retired in 1966.

Hugo Benioff (1935) is an American seismologist. He is famous for his work on

deep focus earthquakes and how they are associated with subduction zones. He

was the first to propose that subduction zones cause deep focus earthquakes.

React on each paragraph. What ideas or principles can your add to these?

Article 3 :

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At first Alfred Wegener's idea about continental drift were rejected.

It was not until the 1960's where scientists began to except his ideas.

One of the largest geographic association called "American Association of

Petroleum Geologists" criticized his ideas. His father-in- law who was a

famous meteorologist also criticizes his ideas. Geophysicists and

American geologists such as George Gaylord Simpson and Sir Harold

Jeffrey also rejected his ideas about continental drift. They first rejected

him because he was not able to find an adequate mechanism to explain

continental drift. Later, when he suggested two mechanisms such as

"Pohlflucht" which means "flight from the poles," explains why continents

seemed to drift towards the equator. Another mechanism was that

explained that the tidal force was moving the continents. Even after

having those mechanisms, his ideas were disapproved. These people

rejected Alfred Wegener's ideas because they thought that the tidal force

was too weak to move the continents. Alfred Wegener's lack of age and

lack of experience in geology was another reason why his hypothesis was

rejected. After Wegener's death scientists started to accept his

hypothesis. Geologists like Harry Hammond Hess found proof of

accepting the concept of continental drift. He proposed an idea of seafloor

spreading. Paleomagnetism was developed in the 1950s which showed

"that rocks in different continents appeared to have different directions of

magnetization, as if continents had drifted apart from each other." His

ideas of seafloor explain that "the ocean floor is constantly being created

at underwater ridges in the middle of the oceans, spreading outwards,

and being consumed in trenches underneath the continents." At last in

the 1960s the continental drift had began to be accepted by the entire

earth science community. It took a lot of time for Wegener's hypothesis to

become the foundation for a revolution for geologist, but it was accepted

later. Source : http://alfredwegener10.blogspot.com/2010/04/who-

opposed-alfred-wegener-and-why.html

If you will be asked to write your own theory that will explain the possible

causes in the movement of plate tectonics, what would it be? Will you

use this Wagners theory? Why ?

Article 4

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Choose the letter of the correct answer.

1. Where does seafloor spreading occur?

A. Mid-ocean ridges C. divergent boundaries between two oceanic

B. Oceanic rift zones D. convergent boundaries

2. The heat process caused by the uneven distribution of thermal energy in

Earth’s interior is called

A. Ridge push C. slab pull

B. Seafloor spreading D. mantle convection

3. What was the name of the super continent that existed 250 million years?

A. Eurasia C. Pangea

B. Disneyland D. Wegenerland

4. Earth’s crust is being actively recycled. Where is new oceanic crust created?

A. At convergent boundaries

B. At mid-ocean ridges

C. At subduction zones

D. At transform boundaries

5. Which of following observations about landforms best supports the theory of

plate tectonics?

A. Volcanoes are distributed randomly on every continent.

B. As lava cools on Earth’s surface, it forms a variety of igneous rocks

C. Impact craters have been found both on dry land and on the ocean

floor

D. Mountain ranges sometimes appear to be continuous on opposite

sides of an ocean.

Learning Task : Study the articles below Answer the questions below .

Write your answer in your notebook.

A

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Line of Evidences that support Plate Movement

Lesson

I

In this lesson, will understand the evidences of plate movements. It

provides you scientific knowledge that will help you explain these evidences. It

also consists of activities that will help you develop your critical thinking skills

to have a deeper understanding about the planet where you live.

Do you know some of the ideas presented by Alfred Wegener? He

proposed that the continents were not stationary but actually moving or

drifting away from one another. His primary sources of evidence included 1.

the tilt of the continents , 2. locations of fossil fuels 3. glacial till deposits and

4. the shift of climates over time. These principles are considered and

accepted in 1970 after all the principles on magnetic shifts, convection

currents and sea floor spreading were integrated in the so called Plate

Tectonics Theory .

There is a variety of evidence that supports the claims that plate

tectonics accounts for (1) the distribution of fossils on different continents, (2)

the occurrence of earthquakes, and (3) continental and ocean floor features

including mountains, volcanoes, faults, and trenches. The continents fit

together almost like puzzle pieces forming Pangaea (one super-continent).

Fossils on different continents are similar to fossils on continents that

were once connected. When the continents split, different life forms developed.

Most continental and oceanic floor features are the result of geological activity

and earthquakes along plate boundaries. The exact patterns depend on

whether the plates are converging (being pushed together) to create mountains

or deep ocean trenches, (diverging) being pulled apart to form new ocean floor at

mid-ocean ridges, or sliding past each other along surface faults.

Most distributions of rocks within Earth's crust, including minerals,

fossil fuels, and energy resources, are a direct result of the history of plate

motions and collisions and the corresponding changes in the configurations of

the continents and ocean basins.

Week

8

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Line of Evidences

Explanations

Fossil

Coastline matching

Paleomagnetism

Age, Heat and Magnetic orientation

Earthquakes and

Volcanoes

Learning Task 1 :Complete the table below by providing the needed

information about each evidence of plate movements. Write your answer in your

notebook.

D

1. One of the first lines of evidence suggesting the existence of plate tectonics was

the discovery of very similar fossils in rock masses separated by vast distances and by

ocean expanses. It suggested that those land areas had in the past been connected.

2. The similarity of coastlines for different continents suggests that they may once

have been connected. But the fact that they were separated by sometimes thousands of

miles suggested continental drift or plate tectonics.

3. The magnetic North and South poles of the Earth correspond closely, although

not exactly, with the spin axis of the Earth. Although the mechanism of generation of

the magnetic field, called the geodynamo, is not fully understood, it is clear that it has something to do with the rotation of the Earth and the presence of mobile materials

with significant electrical conductivity which can circulate.

4. Earthquakes don’t occur randomly across the world, but happen across limited belts which also contain most of the world’s volcanoes. These belts mark the location

of plate boundaries. These areas are so active because the stress of 2 plates against

each other and eventually gives in the form of a volcano or earthquake. The largest belt of activity is the “Ring of Fire” surrounding the Pacific Ocean which is home to

90% of all quakes.

5. As we travel farther and farther out from the spreading center the rocks get older and older, and the magnetic orientation of the rocks changes with the magnetic

pole reversals.

Learning Task 4 : Read the following paragraph. Determine whether these

statements are correct. Justify your answer if it is correct. If it is false, try to

explain what makes the statements wrong.

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PIVOT 4A CALABARZON

Learning Task 3 : Make a mind map showing the different evidences

of plate movements. You may include pictures or phrases to describe and

show your understanding of the theory. Write your answer in your

notebook.

Learning Task 2 : Study the two pictures. Create a two sentence

description of these pictures. You may use any available reference like books,

textbooks and learners material to develop or create your answer.

I

References Printed Materials: Acosta, Herma et al. (2015). Science Leaners Materials, Department of

Education

Electronic Sources: https://www.google.com/search?tbm=isch&sa=1&ei=DoCWW823EtGqoA

Tc16oo&q=picture+of+west+valley+fault&oq=picture+of+west+valley+fault&gs _l=img.3...214558.222918.0.226751.30.29.1.0.0.0.207.3563.0j26j1.27.0....0 ...1c.1.64.img..2.18.2298...0j35i39k1j0i67k1j0i8i30k1j0i24k1.0.t32dYOBLYF s#imgrc=9KRzzp6PJk0-qM:

https://www.google.com/search?tbm=isch&sa=1&ei=DoCWW823EtGqoAT

c16oo&q=sierra+madre&oq=sierra+madre&gs_l=img.3..0i67k1l2j0l8.170773. 174624.0.175111.12.8.0.4.4.0.166.956.0j7.7.0....0...1c.1.64.img..1.11.1002...

35i39k1.0.R7CbQGeGkgE#imgrc=Qg-4iNwAwT7muM:

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For inquiries or feedback, please write or call:

Department of Education Region 4A CALABARZON

Office Address: Gate 2 Karangalan Village, Cainta Rizal

Landline: 02-8682-5773 local 420/421

Email Address: lrmd.calabarzon@deped.gov.ph

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